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PERFORMANCE AND ANCHORAGE OF ROOTSTOCK-SCION 

 COMBINATIONS UNDER HIGH MOISTURE CONDITIONS 



Duane Greene 

 Department of Plant and Soil Sciences 



Research results and grower observations are continually re- 

 confirming reports that apple trees grown on size-controlling 

 rootstocks are more productive, precocious and efficient. However, 

 much information is still needed so that fruit growers can improve 

 production by more intelligent choice of rootstocks for future 

 plantings. 



In 1964 and 1965, a rootstock trial involving six rootstocks 

 and five varieties replicated eight times was initiated at the 

 Horticultural Research Center in Belchertown, Massachusetts. Root- 

 stock and scion selections were made to include those that, at 

 the time, appeared to hold the most promise for fruit growers in 

 New England. All rootstock-scion combinations grew well for the 

 first six years. During the first four growing seasons of the 

 1970's, above average rainfall was experienced that resulted in 

 waterlogged soil conditions for much of the year. In addition, 

 high winds from tropical storms in August of 1970 and 1971 blew 

 over a considerable number of the trees in this experimental plant- 

 ing. Although the damage invalidated much of the data for which 

 the trial was established, it did provide an excellent opportunity 

 to compare the anchorage and to qualitatively evaluate the per- 

 formance of the rootstock-scion combinations under high moisture 

 conditions . 



Table 1 shows the percent trees of each rootstock scion combin- 

 ation that were blown over during these two storms. These data 

 confirm earlier reports that trees grown on M 7 were poorly an- 

 chored particularly when Red Delicious was the scion variety. All 

 eight trees were uprooted by the wind. The Niagara/M 7 combina- 

 tion was also poorly anchored. The only other combination that 

 appeared to be poorly supported was Red Delicious/M 2, where 57% 

 of the trees were tipped over by the wind. To the contrary, all 

 varieties on MM 106 and seedling roots remained well anchored. 



Table 1. Effect of Rootstock-Scion Combination on the Anchorage 

 of Trees Grown at the Horticultural Research Center, 

 Belchertown, Massachusetts. 



^Replicated 6 times 

 ^Replicated 7 times 



